BACKGROUND: Cancer is commonly a disease of the elderly, and elderly cancer patients tend to have worse outcomes than their younger counterparts. This is likely due, at least in part, to the myriad of noncancer problems that tend to accrue with age. SPECIFIC AIMS: Among elderly patients with colorectal cancer, we will identify the relation between comorbid conditions (heart disease, chronic obstructive pulmonary disease (COPD), and diabetes) and: Cancer stage at the time of initial diagnosis; 1. Use of surgical resection, adjuvant therapy, and surveillance colonoscopy; 2. Effectiveness of surgical resection and adjuvant therapy; 3. Probability of death, hospitalization, or diminished quality of life; and, 4. Patient and physician treatment preferences and goals of therapy. RESEARCH PLAN: Initially, we will use the population-based SEER-Medicare linked database, which combines tumor registry information with Medicare administrative data. We will explore how heart disease, COPD, and diabetes impact patterns of care, treatment effectiveness and outcomes of elderly colorectal cancer patients. We will then conduct a qualitative study of patients who have colorectal cancer as well as one of the three comorbid conditions of interest. We will identify how physicians and patients incorporate comorbid conditions into their treatment preferences and goals. This will be followed by additional exploratory analyses and grant-writing . CAREER DEVELOPMENT PLAN: My career goal is to become an independent investigator, applying rigorous clinical research methods that incorporate the principles of geriatrics into the study of elderly patients with cancer - specifically on how non-cancer conditions affect elderly patients. I will work closely with my mentors and a skilled multi-disciplinary team, completing a rigorous program of research, coursework, and independent study. SIGNIFICANCE: This work will generate clinically relevant new insights about the impact of comorbid illness on elderly patients with colorectal cancer, and guide future efforts to enhance communication of treatment preferences and goals in this vulnerable population .